Kohlrabi is a strange and quite pretty vegetable related to broccoli and cabbage. You can peel it and eat the crispy, slightly sweet swollen stem raw, or it can be cooked in mixed vegetable dishes or soups. It is good diced into salads. One of our apprentices ate raw slices with peanut butter, describing it as a little "celery-like" and similarly good with peanut butter. There are also a number of cooked kohlrabi recipes. I know my father-in-law grew up eating kohlrabi in soup in Hungary.